1. Field of the Invention
The invention relates to a drive transmission technique to transmit a rotational driving force to a rotator in a device such as an image forming apparatus configured to form an image on a medium.
2. Description of Related Art
A conventional image forming apparatus, such as a printer, a copy machine, a facsimile machine, or a MFP (Multi-Function Peripheral), configured to form an image on a recording medium, includes a drive transmission device for an image forming unit. The drive transmission device includes: a driven member, which is a drum flange provided at an axial end of a photosensitive drum (image carrier) and having a conical concave gear; a driving member, which is a drive shaft flange provided at an axial end of a drive shaft and having a conical convex gear configured to interlock with the conical concave gear of the drum flange; and a coupling mechanism configured to couple the conical convex gear with the conical concave gear with a biasing member such as a spring to drive the photosensitive drum to rotate with the drive shaft (for example, see Japanese Patent Application Laid-Open No. 09-134094).